Journal APS Oct 2017

J ournal of the A merican P omological S ociety

222

separately subjected to a two-way analysis of variance (ANOVA). Location and grafting date interaction was significant, so data were examined by nursery condition with a one- way ANOVA and means for grafting dates were compared with Duncan multiple range test. All analyses were performed using the SPSS 17. Results  In 2012, graft success ranged from 44.3- 93.3 % in the open field and 18.3-92.3% in the greenhouse. In the open field, the highest graft success was obtained from grafting on 25 April (93.3 ± 1.7 %). In the 50%

shaded greenhouse, the best grafting success occurred on 5 April, which is 20 days earlier than the open field (92.3 ± 1.7 %) (Table 2). Both years rootstock growth stage was related to grafting date. The longest rootstock shoots were measured on 15 May under both nursery conditions. Graft success and growth stage of rootstock were negatively correlated (Table 1). In the 50% shaded greenhouse optimal success occurred when grafting was performed at the bud break stage on 5 April. However, in the open field, 25 April was the optimal date for success when rootstock’s had 5-15 cm shoots. In both nursery conditions lowest graft success occurred on 15 May

Table 1. Correlation coefficients (r-values) between graft success (%) and some environmental conditions 1 . Table.1 Correlation coefficients (r-values) between graft success (%) and some environmental conditions 1 . Table.1 Correlation coefficients (r-values) between graft success (%) and some environmental conditions 1 .

Mean Temp. of fifteen days after grafting (⁰ C)

Mean Temp. of one month after grafting (⁰ C) Mean Temp. of one month after grafting (⁰ C) -0.615

Mean Temp. (⁰ C)

Growth of Rootstock (cm)

Relative Humidity (%)

Years

Mean Temp. of fifteen days after grafting (⁰ C) -0.532

Mean Temp. (⁰ C) -0.553

Growth of Rootstock (cm) -0.891**

Relative Humidity (%) 0.448

Years

2012 2013

-0.553 -0.914**

-0.92 *

0.365

-0.615 -0.893**

-0.532 -0.920**

-0.891** -0.929**

0.448 0.365

2012 2013

-0.914** 1 Correlations were pulled over all locations and dates. *:p<0.05; **p<0.01 1 Correlations were pulled ov r all locations and states. * :p<0.05; ** p<0.01 1 Correlations were pulled over all locations and dates. *:p<0.05; **p<0.01

-0.893**

-0.920**

Table.2 Graft success for ‘Chandler’ walnut trees as influenced by nursery conditions and grafting dates in two years 2 . Table 2. Graft success for ‘Chandler’ walnut trees as influenced by nursery conditions and grafting dates in two years 2 . Table.2 Graft success for ‘Chandler’ walnut trees as influenced by nursery conditions and grafting dates in two years 2 .

Graft Success (%)

2012

2013

Graft Success (%)

Nursery Conditions 50% Shaded Greenhouse Nursery Conditions 50% Shaded Greenhouse Open Field

2012

2013

15 March z 5 April 15 March z 5 April

25 April

15 May 15 March 5 April

25 April 15 May

25 April 68.0 c ± 0.0

15 May 15 March 5 April

25 April 15 May

81.7 b ± 4.4 78.3 bc ± 3.3

92.3 a ± 1.7

18.3 e ± 1.7 44.3 d ± 2.3

98.3 a ± 1.7

91.7 b ± 1.7 100.0 a ± 0.0

63.3 c ± 7.3

33.3 d ± 3.3 60.0 c ± 5.0

81.7 b ± 4.4 78.3 bc ± 3.3

92.3 a ± 1.7

68.0 c ± 0.0 93.3 a ± 1.7

18.3 e ± 1.7 44.3 d ± 2.3

98.3 a ± 1.7

91.7 b ± 1.7 100.0 a ± 0.0

63.3 c ± 7.3

33.3 d ± 3.3 60.0 c ± 5.0

85.0 ab ± 6.6

93.3 a ± 1.7

96.7 ab ± 1.7

75.00 c ± 5.8

85.0 ab ± 6.6

96.7 ab ± 1.7

75.00 c ± 5.8

Open Field

P

<0.001

< .021

P 50% Shaded Greenhouse Open Field

<0.001 65.1 ± 8.6

<0.021 71.7 ± 7.8

50% Shaded Greenhouse Open Field P

65.1 ± 8.6

71.7 ± 7.8

75.2 ± 5.9

82.9 ± 5.2

75.2 ± 5.9 0.002 0.021 Z Values within years and nursery conditions are means ± standard errors of the means followed by common letters do not differ at the 5% level of significance by Duncan’s multiple range test. z Values within years and nursery conditions are means + standard errors of the means followed by common letters do not differ at the 5% level of significance by Duncan's multiple range test. 82.9 ± 5.2 P 0.021 Z Values within years and nursery conditions are means ± standard errors of the means followed by common letters do not differ at the 5% level of significance by Duncan’s multiple range test. 0.002